<html>
<script>
   function isEmail(val){
   var myreg = /^([a-zA-Z0-9]+[_|_|.]?)*[a-zA-Z0-9]+@([a-zA-Z0-9]+[_|_|.]?)*[a-zA-Z0-9]+.[a-zA-Z]{2,4}$/;
   if(!myreg.test(val))
   	return "not mail";
   return "mail";
   };
   alert( isEmail("iaa$julying.com") );
   </script>
   </html>